Hydraulic power-transmission device.



AGITROBN. HYDRAULIC POWER TRANSMISSION DEVIGB."

APPLICATION FILED PEB. 3, 1913.

Patented Dec. 2, 1913.

L ANDR CITROEN, or rams, FRANCE.

HYDRAULIC POWER-TRANSMISSION IIEVICE.

Losa-eco.

Specification of Letters Patent.

Patented Dee. 2, 1913.

peut-ation med February s, 1913. serial No. 745,922.

To ailwhom traag/concern.' n Be it known that I, ANDR CITROEN, citizenof the French Republic, residing at Paris, Department of the Seine, inFrance, have invented certain new and useful Improvements in andRelating to Hydraulic Power-Transmission Devices; and I do herebydeclare the following to be a full, clear, and exact description of theinvention, .such as will enable othersskilled in the art to which itVappertains to make and use the same.

- Apparatus for transmission of movement to a distance acting by meansof a iuid under pressure consists o-f a transmission or control memberand a'receiving or controlled member which are generally identical inconstruction, the former displaces a fluid and sends it to the latterthrough piping, the fluid acting in this receiver so as to reproduce amechanical movement bearing a definite relationship to that by which thetransmission apparatus was actuated; then, through a second system ofpiping, the fluid returns without pressure to the transmittingapparatus, in such a manner that the same Huid, without any loss, servesindefinitely for. the transmisslon. -By reversing .the direction of themovement ofthe first apparatus, the direction ofthe circulation of thefiuid is reversed and also the'direction of y. displacement ofthe secondapparatus.

Naturally, apparatus constructed to obtain such results should notcomprise any dead points in their movement. It will readily beunderstood that, in these conditions, these apparatus are notirreversible of themselves and that any external action upon themovement of the controlled app-aratus makes itself felt on thecontrolling apparatus. It is possible. to add a purely mechanical deviceof any known kind for obtaining irreversibility while at rest to themechanical control of the transmitting member or to that of the'receiving member, but apart from the fact that it is not always possibleto apply these known devices to the controlled apparatus owing tospecial circumstances, the application of these devices to thetransmitting apparatus presents the vinconvenience of shifting to adistance the point at which the controlled apparatus is blocked and alsoof interposing quite a number of members in addition to the Huid itselfthere yis therefore a tendency for these devices to be retarded in theiraction and to produce considerable hesitation or wavering, they are alsoliableto act inopportunely if the slightest hydraulic' recoil shouldoccur.

The object of the present invention is to obtain irreversibility whilethe transmitting and controlled members or driving and driven elementsare at rest by means of a device acting upon the Huid itself, in suchmanner as to block it when the controlled apparatus tends to displacethe transmitting apparatus, it is constituted by a kind of double valve.

In the accompanying drawing: Figure l is an axial section of the twovalves. lFig. 2 is a section at right angles to the foregoing throughthe axis of one of the two valves, thev individual arrangement of whichis repeated in each. V Fig. 3 is a plan. Fig. 4 is a diagrammatic viewshowing the valve mechanism applied to the driving and driven elementsof a railway switch operating mechanism. In the drawing, the valvemechanism is shown applied to the driving and driven elements of arailway switch operating mechanism, but it lwill be understood that itmay be used in combination with any driving and driven elements of thissame general type.

' The device forobtaining irreversibility consists of two valves 1 1 thestems of which form pistons 2 2. The upper chambers 3 3 of the valvebodies communicate respectively with the controlled apparatus A, (Fig.4,) by` means of tubes with connections 4-4. Thelower chambers 5 5communicate in the same conditions vwith the I transmitting apparatus Bthro-ugh the connections 6 6. The pistons 2 2 which are integrallyconnected with thevalves move in cylinders the upper part 'of which'opens tion, because such a movement could only be transformed into acirculation of the fluid, which is unable to find an issuetoward thetransmitting apparatus. Irreversibility of the apparatus while at restis thus insured in an exceedingly simple manner. Now when thetransmitting apparatus is rendered operative, it is essential thattransmission to the controlled apparatus should be possible. With thisobject assuming for example that the transmitting apparatus is startedfor a given direction of movement it follows that the fluid is placedunder pressure on one side in the chamber 5 for example, while it is notunder pressure in the chamber 5. The effect of this pressure is: 1) tolift the valve l from its seat, thereby enabling the fluid to continueits travel in the canalization toward the controlled apparatus. (2) tolift the valve l also, because the chamber 5 cominunicates with 7 and nopressure prevails either in 3 (apart from the e'ect of the valves willalso be lifted, the valve 1 directly.

and the va'lve l by the action of thegpiston 2.' As soon as the pressureceases to exist in the chambers 5 and 5 and consequently in 7 and 7, thetWo valves fall back upon their seats under the influence of thesprings.

I claim:

l. The combination withahydraulic power power transmission mechanismcomprising :driving and driven elements, and supply and 'return conduitsconnecting said elements, of `valves located in said conduits, saidvalves yadapted to be opened by the pressure of the .Huid from thedriving element, but not by that from the driven element when the latteris used as a driving element, and means transmission mechanismcomprising driving and driven elements, of means to prevent the drivenelement from actuating the driving element, said meansl comprising valvecasings, valves located therein, each casing being in communication withthe driving element on one side of the valve and with the driven elemento-n the other side of the valve, `said valves adapted to open in thedirection of ow of the fluid fro-m the driving element, and meansassociated with said,

casings whereby when one of the valves is opened by the pressure of thefluid from the driving elementthe other valve will be opened topermitthe fluid to return to the driving element. 2. The combinationwith a hydraulic fing elernent to act on said o'pen its valve.

power transmission mechanism comprising driving and driven elements, ofmeans toprevent the driven element from actuating the driving element,said means comprising valve casings, val-ves located therein, eachcasing being in communication with the driving element on one side ofthe valve and with the driven element on the other side of the valve,said valves adapted to open in the direction of flow of the fluid fromthe driving element, piston's'on said valves,"said casings provided withopenings in which said pistons are guided, and nieans to permit aportion of the Huid from the driving element to act on the piston of oneof said valves'to open the same.

3. The combination with a hydraulic power transmission mechanismcomprising jdriving and driven elements, of means to prevent the drivenelement from actuating the driving element, said means comprising Valvecasings, valves located therein, each casing being in communication withthe driving element on one side of the valve and with the driven elementon the other side of the valve, said valves adapted to open 1n thedirection of iow of the fluid from the driv- 'ing element, a piston onone of said valves, 4the casing provided with an. opening in which saidpiston is guided, and means to permit a portion of the fluid fromthedrivpiston and thereby 4. The combination with a hydraulic wherebywhen the valve in the supply conduit is opened thevalve in the returnconduit will also be opened.

In testimon whereof I affix my signature, in presence o two Witnesses.

ANDR CITROEN.

Witnesses: Y

HANsoN C. CoxE,

EMILE KLoTz.

